Influence of temperature on the metabolism of Pleuroncodes monodon (Crustacea: Anomura)

AVALOS, CECILIA; HEILMAYER, OLAF; THATJE SVEN,; GUSTAVO ALEJANDRO LOVRICH

Lima, Perú

Simposio; INCO-UE-CENSOR Endterm Symposium; 2008

Universidad Agraria La Molina

Pleuroncodes monodon is a galatheid crab of ~10 cm total length that plays a key ecological role inthe Eastern Pacific Ocean of Chile and Peru as it is a key prey for fishes, birds, and mammals. P.monodon constitutes one of the main crustacean fisheries and is used for human consumption andother byproducts. Although plenty of information on the species related to abundance and distributionis available not much is known about its physiological capability to adapt to changes in temperature.This study aims to determine the standard metabolism, the specific dynamic action (SDA), andenzymatic activity of P. monodon acclimated to four different temperatures.Specimens of P. monodon were caught off Antofagasta (23ºS), Chile, by scuba diving at ~15 m depth.Animals were acclimated to 12º, 16°, 20°, and 24°C over~ 6 weeks and oxygen consumption wasmeasured. An intermittent flow system was used for respiration measurement. Oxygen content wasdetermined with microoptodes connected to a Presens OXY-4-array. After standard metabolism wasmeasured, animals were fed and SDA was determined. Animals were dissected after respirationexperiments, and gills and muscles were frozen to determine activity of citrate synthase and pyruvatekinase.We will present the results from respiration experiments; samples to determine enzymatic activity arecurrently being analyzed. Results on standard metabolic rate at every temperature and the differenceamong them will be presented. We will also show the total net post-pandrial increase in oxygenuptake, the peak rate and the time response at every temperature. The data will be dicussed in thecontext on thermotolerance of galatheids and decapods and within the ENSO context.